U.K. nationals/PhD: Stuck in the Mud: The Role of Saltmarshes in the Long-Term Accumulation and Dispersal of Microplastics across Urban Catchments

University of Nottingham

Nottingham, , GB

Secondary Supervisor: Dr Barry Lomax Nottingham University, Dr Christopher Vane British Geological Survey

Subject Area: Biosciences, Environmental Sciences

Research Title:  Stuck in the Mud: The Role of Saltmarshes in the Long-Term Accumulation and Dispersal of Microplastics across Urban Catchments

Urban estuaries are recognised as major plastic transport corridors connecting terrestrial plastic sources to coastal and marine habitats. Intertidal areas (i.e. salt marshes) accumulate a wide range of throughflow anthropogenic pollutants, including microplastics. As such, these habitats are likely to play an important role in the fate-transport pathways of microplastics yet, they remain understudied.

This project will explore the interaction between tidal waters-marsh vegetation-sediment grain size and plastic pollution in order to understand whether marshes act as short, intermediate or long-term stores of plastic. For example, the role the played by vegetation as trapping sites for microplastics and their subsequent degradation and break down has only been recognised recently. Down-core variations in legacy and emerging organic pollutants underpin ecosystem health risk assessments but can be due to changes in formulations and input concentrations. Similarly, analysis of microplastics, within saltmarsh cores, has the potential to act as a geochronological tool for identifying changes in both plastic depositional/accumulation rates and processes within the wider catchement, reflecting changes in anthropogenic activity and climate events. 

This study will investigate and develop an accumulation record of microplastics in saltmarshes through time, investigating both changes in composition and abundance. The successful candidate will develop novel methodologies and be trained in a wide range of ecological and laboratory-based methods. This will involve using an imaging CT scanner to link vegetation ecology and dynamics (i.e. root density) with microplastic characteristics, alongside an understand of the relationship between sediment size and microplastic entrapment size. This has the potential to offer new insights into plastic transport pathways and aid in environmental conservation efforts, including the use of saltmarshes as nature-based solutions.

Training: The successful candidate will use a mixture of natural and reclaimed saltmarsh sites across the River Thames as a ‘living laboratory’ to explore controls on spatial and temporal abundances in microplastics. This will be delivered by collecting sediment cores along transects for microplastic separation. Density, separated microplastics will be chemically characterised using a range of techniques including single point and focal plane imaging Fourier-Transform Infrared Spectroscopy (FTIR) and Rock-Eval pyrolysis. The resulting chemical, physical and imaging data-sets will be evaluated using multivariate statistics to explore connections and ultimately explain the key processes controlling accumulation and release of plastic in salt marshes in urban estuaries.

Award Start Date: 20th September 2021

Duration of Award: 48 months

Terms and Conditions: 36 months funded

Applicant Qualification Requirements:

Applicants should have an interest in aquatic science, environmental science, biology or ecology. They should hold, or be expected to obtain, a minimum of a UK Honours degree at 2:1 or equivalent in a biological or environmental science subject. Candidates with an additional qualification (i.e. Masters) will be looked on favourably.

The successful applicant will be required to transport soil cores from London to Nottingham so ideally will hold a full driving licence.

Swimming competence and experience of laboratory and fieldwork will be essential.

How to Apply: Cover letter explaining why you feel you are a suitable candidate (maximum 1 page), alongside a curriculum vitae should be emailed to [email protected]